Files
impala/testdata/workloads/functional-query/queries/QueryTest
skyyws ad29ce70b3 IMPALA-11040: Remove unnecessary reset() method in class 'UnionStmt'
When query contains multiple nested union stmt, more than twenty or
thirty, and needs 'reAnalyze', such as rewrite expr. Query would
execute slowly, even failed due to 'reset' method called in class
'UnionStmt' and 'SetOperationStmt'.
'SetOperationStmt' is added in IMPALA-9943 and IMPALA-4974. Multiple
nested union stmt will lead to 'reset' called numbers to grow
exponentially. Since 'operands_' will be reset in two class' reset()
method, and handle with their children recursively. Too many nested
union stmt will cause deep nesting.
UnionStmt.reset() content is exactly same as SetOperationStmt.reset().
This patch  removed this method in 'UnionStmt'. After this, the
original query would execute quickly.
An example already add in file 'union.test', without this patch, the
example query would execute slowly, or even fail.

Testing:
- Added new test case in 'union.test'

Change-Id: I408a396d40d9622f2ae6c459f49cbfcc19affd14
Reviewed-on: http://gerrit.cloudera.org:8080/18061
Reviewed-by: Qifan Chen <qchen@cloudera.com>
Reviewed-by: Zoltan Borok-Nagy <boroknagyz@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
2021-12-09 23:17:20 +00:00
..
2021-07-06 18:35:30 +00:00
2021-02-15 22:25:41 +00:00